In electronic equipment, a component may exhibit non-linear characteristics that degrade the performance of such equipment. Special care must be taken when designing this component as operating only in a linear region of the component results in lower efficiency of the component. For example, power amplifiers that are used to amplify a signal prior to its transmission often reveal a non-linear distortion of the transmitted signal when used for excessive amplification, i.e., gain outside the linear gain region of the amplifier. Traditionally power amplifiers had to be linear, for example of class A type, which resulted in a very low power efficiency, i.e., the output power from the power amplifier is far from the saturated power of the power amplifier.
The non-linear behavior of a non-linear component creates distortion of the signal produced by such component. The distortion may be handled by performing digital pre-compensation of the signal or pre-distortion of the signal. A digital pre-compensation is carried out by a Digital Pre-Distorter, DPD, which compensates for the distortion introduced by the non-linear component. Non-linear distortion mitigation such as with DPD involves finding pre-distortion parameters, even in the presence of noise. Finding the optimal pre-distortion parameter in the presence of noise is difficult. Moreover, as the order of non-linearity of the non-linear component grows, so does the complexity of the pre-distortion solution. State-of-the-art DPD algorithms tend to present convergence issues, be associated with bias problems in the presence of noise, and/or be quite complex.
At least partly due to the above, there is a need for a distortion mitigation solution with improved convergence and/or reduced complexity to be used with the non-linear component.